Wavecom W74PC V8.7.0 - Manual (Page 151)

WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V8.7.0 Transmission Modes
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Parameter Value
Frequency range HF
Operation modes Duplex ARQ
Modulation MFSK-36
Speed 25, 50 or 100 ms
Receiver settings DATA, CW, LSB or USB
Input format(s) AF, IF
CIS-36 is operating with Symbol rates of 10, 20 or 40 Bd which is equivalent to tone duration of 100, 50
or 25 ms.
Transmissions in CIS-36 are mostly in Russian using an ITA-2 alphabet. CIS-36 is a full-duplex mode with
two transmission frequencies, but can also be used in simplex mode.
CIS-36 is based on the older PICCOLO-MK1 system. However, the signal is not symmetric and uses three
frequency groups with 10, 11 and 11 frequencies. The tone spacing is 40 Hz. The theoretical bandwidth is
1400Hz.
In on-line crypto traffic mode the control tones #1, #12, # 24 and #36 are rarely sent so between the
three frequency groups a spacing of 80 Hz seems to appear.
The decoder shows the shift cursors at the tone position #2 and #35 (resulting in a 1320 Hz shift).
The 10 Bd variant is used for manually transmitted operator messages and is mostly unencrypted. The au-
tomatic switching of the tone length is initialized by control sequences.
When message traffic has to be sent, the system switches to 20 or 40 Bd. This part is either coded or
online encrypted in almost every transmission. Special control sequences are used for transmission con-
trol, call set up and clearance.
CIS-36 also has SELCAL and link establishment features.
CIS-36-50
CIS-36-50, also known as BEE-36 or T600, is a synchronous system. Usually a 36 Bd idle sequence is
transmitted, followed by 50 baud traffic.
Parameter Value
Frequency range VLF, HF
Operation modes Simplex
Modulation FSK
Symbol rate 36, 50, 75, 100, 150 Bd
Shift 85, 125, 250 and 500 Hz, variable 50-3500 Bd
Receiver settings DATA, CW, LSB or USB
Input format(s) AF, IF
All traffic is encrypted.
A message begins with a bit synch sequence and a start-of-message preamble. Message data is sent with
a 7-bit, 3:4 ratio alphabet, and ends with an end of transmission sequence containing at least 4 end-of-
transmission characters.
The length of a message is variable. If a transmission contains more than one message, the start of mes-
sage sequence is left out between messages.
Occasionally traffic with call signs in FSK CW is transmitted.